This invention relates to a recording material capable of forming a color image by use of photohardenable microcapsules and to a process for the formation of a color image by the use of said recording material.
Known processes for the formation of a color image include silver salt photographic processes excellent in resolving power and nonsilver processes such as electrostatic recording processes and electrophotographic processes. Although inferior in the quality of color image to the silver salt photographic process, the non-silver process is capable of tone reproduction and is used in the reproduction of color images.
Such known processes, however, are complicated in the operation to produce a color image and need an equipment of large size which requires an elaborated maintenance, thus resulting in an increase in the cost of reproduction.
Further, the recent progress in computers aroused a demand for reproducing as a hard copy the color image displayed on cathode ray tubes (CRT) or the like, thereby to allow the color image to be observed closely by holding the hard cpy in observer's hands. To meet the demand, there have been shown several processes for the formation of color images by converting the image into electrical signals. Representatives of such processes are a thermal transfer process and an ink-jet printing process. In the former process a thermal head is used to transfer to an image receiving sheet at least one color from a transfer sheet coated with a plurality of coloring materials. Although the equipment is small in size and is free of maintenance, this process has disadvantages in that the sharpness of reproduced image is unsatisfactory because the resolving power depends on the size of heated part of the thermal head, and an additional labor is required in the disposal of waste transfer sheet after the image formation.
In the ink-jet printing process, an image is formed on the image receiving sheet by the impingement of flying ink droplets delivered from nozzles. This process has disadvantages in that the nozzles are susceptible to clogging with the ink and at least three nozzles are necessary because inks of different colors must be delivered from independent nozzles.
There is, therefore, a strong desire for the development of a process for the formation of a color image, which is simple in the procedure and requires an equipment small in size and free of maintenance. Japanese Patent Application "Kokai" (Laid-open) No. 230,786/84 discloses a process for the formation of a color image to meet the above desire. Unfortunately, this process is insufficient in the image resolution.